But a 360 built to equivalent specs will out run a 340 any day, it's got 20 more cubic inches. Even the 5.2L (318) magnum motor used in the trucks up until the 5.7 hemi makes more HP than the 340's did.
You have to remember that mopar engines up through 72 were rated on gross HP, that is, no alternator, no water pump, no exhaust, no air cleaner. After 72 the numbers were net which ment alternator, water pump, exhust, air cleanre, etc.
FWIW, mopar is selling what they call a 340 block but this block but this block is ment for serious big cube engines and can support over a 4.1" bore which allows them to sell a 440 small block.